Bowgun

The Bowgun is a special pistol-style crossbow. It shoots explosive Bowgun Bolts at the target which detonate on impact. You must reload after each shot. The Bowgun takes up 15 cells (3x5) in the Attache Case.

You can only obtain it in the bonus mission Separate Ways. Buy it from The Merchant for 70,000 PTAS in Chapter 3 - Retrieve The Sample